Conventional conveyor belt cleaning devices generally include one or more blades disposed in a plane transverse to the conveyor belt which are urged toward the belt so as to cause engagement of the blade, such as on an edge, with the belt surface. These devices generally are designed to allow the scraper blades to move in reaction to passing obstructions such as mechanical belt fasteners and damaged belt covers, as well as to the changing surface of the belt. This desired “range of motion” is often hampered by cargo material removed from the belt, but clinging to the cleaning device and its own support structure, which is commonly directly below the cleaning blades.
The clinging material negatively affects the efficiency of the cleaning device in various ways. The impact of the oncoming cargo on the blades reduces the effective pressure of the blade to the belt. Also, the weight of the clinging material is a negative to the required cleaning pressure. If this negative load is compensated for by increasing the operating pressure of the device, then the device will experience excessive pressure when the adhering build-up either falls away, or is washed away by increased moisture on the belt, or by clean-up operations. Further problems arise when adhering materials can set hard due to being left on an inoperative device overnight, or during any lengthy shutdown of the system.
Another problem encountered by many such devices, is that when a wear resistant blade, such as tungsten carbide, is struck by a fast moving obstruction such as mechanical belt fasteners or damaged belt covers, the blade is deflected back and away from the belt surface. The scraping device is designed to return the blade to engagement with the belt. This re-engagement can cause cutting of the belt cover, due to the amplified return force of the blade.
In spite of their long term use there is still an ongoing desire for improved conveyor belt cleaning devices. Improvements in a conveyor belt cleaners are provided herein.